Polishing disk



`lune 3, 1930. G, LDORF- 1,761,890

' POLISHING DISC Filed March 16, 1928 Y. Inventor.- @WV 2f Patented June 3, 1930 UNITED STATES GUSTAV L'DOBF, OF BARMER', GERMANY, ASSIGNOB T0 ABTUB, SCHULTE, 0F 'VEL- IBERT, GERMANY, KARL KCH, F BARMEN', GERMANY, AND WILHELM HOF, 0F

ELBERFELD, GEB/M N'Y POIISHING DISK .Application led March 16, 1928, Serial No. 262,306, and in Germany December &8, 1926.

Ivhave filed a patent application in Germany on December 28, 1926; in Austria on February 6, 1928; in En land on February 8,

1928; in Switzerland on ebruary 9, 1928 in The necessary thickness in such disks hasv hitherto been obtained by superimposing a suitable number of turns of the spiral band in a continuous coil.

' There are therefore, certain practical disadvantages inherent in these known polishing disks in that firstly they can only be impregnated with diiiculty, secondly that on polishing with such disks, there is a danger of the free end of a spiral band extending in the direction opposite to the direction of rotation of the polishing disk, remaining attached advantage is that on polishing cumbersome or awkwardly shaped objects, the portions of the work projecting between the layers of the disk are entrained in the direction of the rise of the layers helically wound, so that a force must be used on supporting the work, which opposes the lateral force exerted on the work. This, however, results in quick wear or destruction of the polishing disk.

These objections are overcome by the present invention, by forming the polishing disk of a number of layers each consisting of a section of the spiral band converted into the form of a plane disk, corresponding to asingle convolution of the band.

The spiral band produced for example continuously on a suitable ribbon loom, is accordinglycut up intov single turns and each individual single turn is then converted into the form of a plane, plate or disk, in which the radial slit may be left open or closed in any suitable manner, for example by stitching.

A suitable number of the individual bands or disks thus obtained, forming separate turns of the 'spiral band, are then superimposed until the desired thickness of the polishing disk is obtained, the radial lines of cut in the various layers being preferably relatively displaced.

The layers formed of individual disks can be held fast on the axis of rotation by the two flanges, without any further means of connection or can be previously stitched together 1n known manner.

The line. of cut of the disk sections may be closed up in a special manner by means of strips of fabric stitched thereon. Disks of fabric of suitable size may also be stitched on other disk-shaped sections of the spiral band on one or both sides.

The invention is more particularly described with reference to the accompanying drawings in which Figure 1 shows several continuous convolutions of a spiral band, forming a known type of polishing disk.

Figure 2 is a view of the disk shown in Figure 1l but with the convolutions of the own type of disk.

Fig. 3 shows a number of separate disks cut from the spiral band according to the present invention.

ig. 4 is a view showing these disks placed 1n juxtaposition.

ig. 5 is a View of a single disk showing the line of cut of this.

t band placed in juxtaposition to form the to the object to be pollshed. A further dlskn Fig. 6 is a similar view showing a form of completing the disk after it has been cut from a spiral band.

Fig. 7 is a Inodication.

In the old types of polishing disks as shown in Figs. 1 and 2, the device consists of a plurality of continuous convolutions of a single spiral band, these convolutions being shown at 1, 2 and 3. The convolutions are pressed together as shown in Fig. 2 in order to form the completedl disk, the ends of this being indicated at 4 and 5 respectively and the layers of material being arranged transversely of the axis of rotation 6. One end 5 lies on the outer radial face of the disk 3 and the end 4 lies on the outer radial face of the disk 1.

According to the present invention the convolutions ofthe known type of disk are cut up along a plane indicated by the reference 7 in Fig. 1. By this means a. plurality of 1ndividual and separate plates or disks 1, 2 and 3 are formed as indicated in Fig. 3, the halves of each convolution being relatively displaced in order to bring the radial cut edges of each convolution together as at 7 to form the plate or disk. lhe disk, when completed is shown in Fig. 4.

As will be seen from a study of Fig. 3, the joining line for one disk extends radially from the centre in a different direction to the joining line 7 of the next disk so that When the three disks are placed together these lines are not superimposed. l

In the construction shown in Fig. 6 the line of section 'i' is closed by means of a strip of fabric 8 stitched thereto.

In the modified form of construction shoWn in Fig. 7 disks of fabric 9 of suitable size are stitched on one or both sides of the disk shaped sections of the spiral band. Y

The spiral ribbon material used in constructing the polishing disk of the present invention can be obtained byweaving, knitting or any other suitable process.

I claim:

1. A polishing device comprising a plurality of layers of a fabric originally manui actured as a spiral band, each layer' consisting of a section corresponding to a single Cspilral convolution converted into a plane :2. A polishing device as claimed in claim 1 having the radial lines of section of the individual plane disks relatively displaced in the various layers.

3. A polishing device as claimed in claim 1 having the lines of section of the individual plane disks relatively displaced in the various layers and closed by means of strips of fabric stitched thereto.

4. A polishing device as claimed in claim(` 1 having disks of fabricv of suitable size stitched on one or both sides of the individual plane disks. y I,

5. A method of forming a polishing device consisting in preparing -a continuous spiral band, cutting said band in a plane containing the axis of the band, connecting the ends of each convolution together to form a plurality of disks and placing together said individual disks in close relationship.

6. A method of preparing a polishing device substantially in the form of a disk consistp ing in forming a continuous spiral band, cut

ting this band in a plane, the edge of which coincides with the axis of the band, joining together the edges of each convolution so cut 'to form a plurality of individual disks and placing said disks in juxtaposition so that the lines of cut of adjacent disks extend in varying radial directions.

In testimony whereof, I havek signed my name to this specification at Cologne, Grer-` 

